Step 1: Understanding the Question:
This is a knowledge-based question from industrial chemistry. It asks to identify the specific catalyst system used in the Haber-Bosch process for ammonia synthesis.
Step 2: Key Formula or Approach:
The Haber process is the industrial method for producing ammonia (\(NH_3\)) from nitrogen (\(N_2\)) and hydrogen (\(H_2\)). The balanced reversible reaction is:
\[
N_2(g) + 3H_2(g) \rightleftharpoons 2NH_3(g) \quad (\Delta H<0)
\]
This reaction is slow and requires a catalyst to proceed at an economically viable rate under manageable temperature and pressure conditions.
Step 3: Detailed Explanation:
1. The Catalyst: The primary catalyst used in the Haber process is finely divided iron (Fe). Using it in a finely divided (porous) form provides a large surface area, which increases its catalytic efficiency.
2. The Promoter: To further enhance the activity and stability of the iron catalyst, a promoter is added. A promoter is a substance that is not a catalyst itself but increases the efficiency of the catalyst. In the Haber process, molybdenum (Mo) is commonly used as a promoter. Modern catalysts often use oxides like potassium oxide (\(K_2O\)) and aluminum oxide (\(Al_2O_3\)) as promoters.
Therefore, the complete catalytic system is typically described as finely divided iron with a promoter like molybdenum.
Step 4: Final Answer:
The catalyst used is finely divided Iron (Fe) with Molybdenum (Mo) serving as a promoter.